A bit of information I missed out of my previous post was that you can only tow an unbraked trailer if it weighs less than 750kg.
There are very few cars in the UK that would come in under that weight.

Some cars without an engine in may come under 750kg.

Towing with a Dolly is only permitted for LOCAL recovery, its still an unbraked trailer, unless the dolly has brakes on it.

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